Method for manufacturing laser hologram paper

ABSTRACT

A method for manufacturing water-based laser hologram papers has acts of entirely or partially coating water-based varnish on a printed paper substrate, subjecting the paper substrate to a mirror treatment, and entirely or partially molding the paper substrate with laser compressing operations. By substituting PVC or PET plastic membranes with decomposable water-based varnish, the laser hologram paper is environmental friendly to reduce pollution and is also breakable to provide counterfeit-deterring efficiency. Moreover, material cost of the plastic membranes is eliminated to reduce manufacturing cost of the laser hologram papers.

This application is a divisional application of U.S. application Ser.No. 11/082,656, filed Mar. 18, 2005.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a water-based hologram paper, and moreparticularly to a water-based hologram paper that is environmentallyfriendly and highly recyclable and has anti-counterfeiting capabilityfor products, and low contamination and low cost in manufacture.

2. Description of Related Art

Conventional paper substances applied for goods containers or packingmaterial are printed with patterns on an outside periphery to increaseappearance attraction to the goods. In order to identify manufacturersor trademarks, laser molding technology is applied to attach lasermembranes on the paper substances to achieve laser hologram papers fordistinguishability from counterfeits. The conventional laser membranesare usually made of polyvinyl chloride (PVC) and polyethylene glycolterephthalate (PET) plastic membranes that are compressed to combinewith the paper substrate. Because of adding the plastic membranes, themanufacturing costs of the laser hologram papers are correspondinglyincreased. Moreover, laser grains on the plastic membranes are easilymis-aligned with printed patterns on the paper substrates when theplastic membranes are processed in forming the laser grains in partialsections, locating the patterns at desired positions and even otherprocesses after printing. Therefore, the resulting mismatch of grainsand patterns causes the quality of the laser hologram papers todecrease. Additionally, the laser hologram papers are barely recyclablebecause separating the plastic membrane and the paper substrate isdifficult and complex and has high operational cost.

By covering them with the plastic membranes, the laser hologram papersin the form of anti-counterfeiting labels can be completely detachedfrom the goods. Therefore, offenders usually peel the laser hologrampapers off and attach them on fake goods to pass them off as genuineones.

With regard to manufacturing methods for the laser hologram papers, fourconventional methods according to different types of laser hologrampapers are described as the following:

1. Transparent laser hologram papers entirely with laser grains: the PETplastic membranes are treated with a corona treatment and then asolvent-based resin serving as a bridging agent is coated on surface ofthe PET plastic membrane after the corona treatment, wherein, the resinis composed of 35±2 wt % acrylate resin, 50±2 wt % isopropanol and 35±2wt % water. The coated PET plastic membranes are subjected to the lasercompressing molding and then combined to a paper substrate with printedpatterns to achieve the laser hologram papers.

However, the PET plastic membranes on the laser hologram papers can notbe recycled and are mostly discarded so that the PET plastic material iswasted and manufacturing cost is high.

2. Transparent laser hologram papers having laser grains in partialsections: the plastic membranes are thermally ironed by means of agilding operation to attach on partial sections of the paper substratesto complete the patterns.

However, the gilding operation is expensive in operational cost and thepatterns are easily mis-aligned so that quality of the laser hologrampapers is low.

3. Aluminum-coating laser hologram papers entirely with laser grains:the PET plastic membranes are treated with the corona treatment and thesolvent-based resin serving as a bridging agent is coated on the PETplastic membranes. Then, the coated PET plastic membranes are subjectedto the laser compressing molding to process a working face and furthercoated with an aluminum film on the working face by means of vapordeposition. After forming the aluminum film, two faces of the PETplastic membranes are coated again with the solvent-based resin and thencombined with a paper substrate to carry out the printing to achieve thelaser hologram papers.

In this method, partial laser grains and the patterns are covered byprint ink which results in the laser hologram papers having poor qualityin appearance.

4. Aluminum-coating laser hologram papers having laser grains in partialsections: the PET plastic membranes are treated with the coronatreatment and then the solvent-based resin serving as a bridging agentis coated on the surface of the PET plastic membrane after the coronatreatment. The coated PET plastic membranes are subjected to the lasercompressing molding with a laser nickel board to form the laser grainsin partial sections at a working face. Then, the working face is coatedwith an aluminum film by means of vapor deposition. Lastly, the treatedPET plastic membranes are coated with the solvent-based resin at theirstwo sides and then combined with a paper substrate to carry out theprinting to achieve the laser hologram papers.

However, laser grains on the plastic membrane and printed patterns onthe paper substrate can not be precisely aligned with each other wherebythe quality of the laser hologram papers is poor.

The present invention has arisen to mitigate or obviate thedisadvantages of the conventional laser hologram papers and theconventional methods for manufacturing the laser hologram papers.

SUMMARY OF THE INVENTION

The main objective of the present invention is to provide a water-basedlaser hologram paper that is environmentally friendly and highlyrecyclable and has anti-counterfeiting capability for products and lowcontamination and low cost in manufacture.

Another main objective of the present invention is to provide methodsfor manufacturing the laser hologram paper above.

Further benefits and advantages of the present invention will becomeapparent after a careful reading of the detailed description withappropriate reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a schematic side view of a laser hologram paper in accordancewith the present invention;

FIG. 2 is a schematic side view of another laser hologram paper inaccordance with the present invention;

FIG. 3 is a schematic operational view showing a method formanufacturing the laser hologram paper in accordance with the presentinvention; and

FIG. 4 is a schematic operational view showing another method formanufacturing the laser hologram paper in accordance with the presentinvention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

A method for manufacturing laser hologram papers in accordance with thepresent invention substantially comprises acts of:

printing patterns on a working face of a paper substrate;

coating the working face with a water-based varnish layer for lasercompressing molding;

thermally compressing the water-based varnish layer to create a mirroreffect; and

laser compressing molding the paper substrate to perform laser grains onthe water-based varnish layer.

Wherein, the water-based varnish is selected from (a) athermal-resistant flatting oil composed of 42±2 wt % acrylic copolymerand 55±2 wt % water, (b) a water-based varnish for laser compressingmolding composed of 42±2 wt % acrylic copolymer, 3±1 wt % soya bean oil(lecithin) and 55±1 wt % water, and (C) a non-thermoplastic varnishcomposed of 50-60 wt % acrylic monomer, 40-50 wt % epoxy acrylateoligomer and 5 wt % photo-initiator.

Another method for manufacturing the laser hologram papers in accordancewith the present invention involves a printing process after the lasercompressing molding process and further contains an aluminum coatingact. This method comprises acts of:

coating a working face of a paper substrate with a water-based varnishlayer for laser compressing molding;

thermally compressing the water-based varnish layer to create a mirroreffect on the working face;

laser compressing molding the paper substrate to perform laser grains onthe water-based varnish layer;

steam coating an aluminum film on the water-based varnish layer by vapordeposition;

coating a water-based resin film on the aluminum film; and

printing an ink layer on the water-based resin film to perform patternsso that an aluminum-coated laser hologram paper is achieved.

Wherein, the water-based resin is a bridging agent and is composed of43±1 wt % acrylic monomer (emulsion of polyacrylate), 45±1 wt % water,and 3±1 wt % ammonium hydroxide.

With reference to FIG. 1, the laser hologram paper comprises a papersubstrate (10), an ink layer (11) and a varnish layer (12) sequentiallymounted over the paper substrate (10), wherein the varnish layer is madeof water-based varnish.

With reference to FIG. 2, the aluminum-coated laser hologram paper has apaper substrate (20), a first varnish layer (21), an aluminum layer(22), a second varnish layer (23), an ink layer (24) and a third varnishlayer (25) sequentially mounted over the paper substrate (10), whereinall varnish layers are made of water-based varnishes.

Preferred embodiments of the methods for manufacturing the water-basedlaser hologram paper are described as the following.

<Transparent Laser Hologram Paper Entirely with Laser Grains>:

A paper substrate is printed by an ink printing to have desired patternson a working face. The working face is entirely coated with water-basedvarnish that is made of a thermal-resistant flatting oil composed of42±2 wt % acrylic copolymer and 55±2 wt % water or a water-based varnishii for laser compressing molding composed of 42±2 wt % acryliccopolymer, 3±1 wt % soya bean oil (lecithin) and 55±1 wt % water. Then,the coated paper substrate is subjected to have a mirror treatment(operational procedures are described later) and lastly undergoes lasercompressing molding operations.

<Transparent Laser Hologram Paper with Laser Grains in PartialSections>:

Procedure I:

A paper substrate is printed by an ink printing to have desired patternsand colors on a working face. The working face is entirely or partiallycoated with a thermal-resistant varnish or a non-thermoplastic varnishand then partially coated with a water-based varnish of lasercompressing molding. Wherein, an endurable temperature of thewater-based varnish is lower than one endurable temperature of thethermal-resistant varnish. The coated paper substrate is subjected tohave a mirror treatment (operational procedures are described later) andlastly undergoes laser compressing molding operations. Therefore, whenmolding temperature is between the endurable temperatures of thethermal-resistant varnish and the water-based varnish, partial areas ofthe water-based varnish melt and can be molded to have the laser grains.On the contrary, other areas coated with the thermal-resistant varnishor the non-thermoplastic varnish can not be molded and have no lasergrains so that the laser hologram paper is partially molded in the lasercompressing molding operations.

Procedure II:

A paper substrate is printed by an ink printing to have desired patternson a working face requiring patterns, then coated with the water-basedvarnish on the working face entirely, and subjected to a mirrortreatment. Lastly, the paper substrate is partially treated by lasercompressing molding with nickel plates having grains molded in part.

<Aluminum-Coated Laser Hologram Paper Entirely with Laser Grains>:

Procedure I

A paper substrate is coated with the water-based varnish on a workingface entirely. The working face is subjected with a mirror treatment andcoated with an aluminum layer by vapor depositing. After forming thealuminum layer, the working face is further coated with water-basedresin and then printed by an ink printing to form a pattern layer withdesired patterns on the working face. Moreover, the pattern layer isentirely coated with a water-based varnish, treated with the mirrortreatment again, and molded by laser compressing operations.

Procedure II

A paper substrate is entirely coated with water-based varnish on aworking face, then subjected to a mirror treatment, and molded by lasercompressing operations. After molding, the working face is furthercoated with an aluminum layer by vapor depositing and then coated withwater-based resin. Lastly, the paper substrate is printed by an inkprinting to have desired patterns or colors on the working face.

Wherein, the paper substrate is cut into regular sheets before printingto make sheeted lithography fluent. Selectively, the paper substrate canbe directly printed by rotary web printing without cutting.

<Aluminum-Coated Laser Hologram Paper Having Laser Grains in PartialSections>:

Procedure I

A paper substrate is coated with the water-based varnish on a workingface entirely, then subjected to a mirror treatment and molded by lasercompressing operations with nickel plates having grains molds in part.Then, the paper substrate is coated with an aluminum layer by vapordepositing and further coated with water-based resin. Lastly, the papersubstrate is printed by ink printing to have desired patterns and colorson the working face.

Procedure II

A paper substrate is coated with a water-based varnish on a working faceentirely, then subjected to a mirror treatment, coated with an aluminumlayer by vapor depositing, and further coated with water-based resin onthe aluminum layer. Then, the coated substrate is printed by inkprinting to have desired patterns and colors on the working face,further partially or entirely coated with a thermal-resistant varnish ora non-thermoplastic varnish, and lastly coated with a water-basedvarnish. Wherein, an endurable temperature of the water-based varnish islower than one of the thermal-resistant varnish. The coated papersubstrate is subjected to have a mirror treatment and lastly undergoeslaser compressing molding operations. Therefore, when the moldingtemperature is between the endurable temperatures of the water-basedvarnish and the thermal-resistant varnish, partial areas coated with thewater-based varnish are thermally molded to have laser grains. On thecontrary, other areas coated with the thermal-resistant varnish or thenon-thermoplastic varnish can not be melted and have no laser grains sothat the laser hologram paper is partially molded in the lasercompressing molding operations.

Procedure III

A paper substrate is coated with the water-based varnish on a workingface entirely, then subjected to a mirror treatment, and coated with analuminum layer by vapor depositing. Then, the paper substrate is furthercoated with the water-based resin, printed by ink printing to havedesired patterns and colors on the working face, entirely coated withthe water-based varnish, subjected to the mirror treatment and lastlypartially molded with layer compressing operations with nickel plateshaving grains molds in part.

Except the operational process of the preferred embodiment in thepresent invention, the mirror treatment is further illustrated as thefollowing:

In order to make the laser hologram papers have deflective efficiency,the mirror treatment is commonly used in treating of the varnish layers.As shown in FIG. 4, a system for the mirror treatment comprises twoconveying wheels (40), a flexible iron belt (42) looped around the twoconveying wheels (40,) and a compressing roller (41) in contact with oneof the conveying wheels (40). The conveying wheel (40) abutting thecompressing roller (41) is heated.

When the paper substrate is fed between the compressing roller (41) andthe heated conveying wheel (40), the working face faces the iron belt(42) to make the varnish layer heated by the conveying wheel (40) andadhere to the iron belt (42). Thereby, the varnish layer possesses amirror effect after thermal compression.

However, the paper substrate easily detaches from the iron belt (42)when the working face is not completely covered with the varnish and thepaper substrate only partially contacts the iron belt (42). Therefore,the quality of the mirror effect on the laser hologram paper is reduced.To overcome the foregoing problem, another system is carried out in thepresent invention that is to place the paper substrate over the ironbelt. As shown in FIG. 3, the system for the mirror treatment alsocomprises two conveying wheels (30), a flexible iron belt (33) loopedaround the two conveying wheels (30), and a compressing roller (32) incontact with one of the conveying wheels (30). The difference betweenthis system and the foregoing one is that the compressing roller (32) islocated over the corresponding conveying wheel (30). Therefore, thepaper substrate is mounted on the iron belt (33) with its working facefacing down to contact with the iron belt (33). By supporting of theiron belt (33), the paper substrate does not fall from the iron belt(33) during the mirror treatment and the paper substrate completelycontacts the iron belt (33) even when the paper substrate is notcompletely coated with the varnish.

According to the above description, the methods and the laser hologrampapers in the present invention have the following advantages:

1. Environmental Friendly:

Conventional laser hologram papers are all made of PET or PVC plasticmembranes attached to a paper substrate. Therefore, the plasticmembranes have to be separated from the paper substrate before theconventional laser hologram papers are recycled. Because the treatingmethod of separating is troublesome and the recycled plastic membraneshave low economic worth, the conventional laser hologram papers aredirectly discarded without treatment and cause environmental problems.In the present invention, the water-based resin performs the coatinglayers that substitute the plastic membranes. The water-based resin isenvironmental friendly and can be naturally decomposed after discarding.

2. Low Manufacturing Cost:

Without using the plastic membranes, material cost of the plasticmembranes is saved for manufacturer.

3. Excellent and Various Appearances:

Conventional methods for manufacturing laser hologram papers haveproblems of mis-alignment between the laser grains on the plasticmembranes and the patterns on the paper substrate. In the presentinvention, the varnish is directly coated on the paper substrate toperform “multiple-laminating” coating without alignment of the plasticmembranes and the paper substrate. Therefore, the laser hologram papercan have more variety in appearance.

4. Counterfeit-Deterring Efficiency:

Unlike the tenacity of the plastic membranes on the conventional laserhologram papers, the varnish layers on the laser hologram paper arebreakable. Therefore, the laser hologram papers will be damaged whensome offenders try to peel the laser hologram papers off to attach themon fake goods.

Although the invention has been explained in relation to its preferredembodiment, it is to be understood that many other possiblemodifications and variations can be made without departing from thespirit and scope of the invention as hereinafter claimed.

1. A method for manufacturing an aluminum-coated laser hologram paper,the method comprising acts of: coating a working face of a papersubstrate with a first water-based varnish layer; thermally compressingthe first water-based varnish layer to create a mirror effect; steamcoating an aluminum film on the water-based varnish layer by vapordeposition; coating a water-based resin film on the aluminum film;printing an ink layer on the water-based resin film to perform patterns;coating a second water-based varnish layer on the ink layer; thermallycompressing the second water-based varnish layer to create a mirroreffect; and laser compressing molding the paper substrate to performlaser grains on the water-based varnish layer.
 2. The method as claimedin claim 1, wherein the laser grains are formed on the water-basedvarnish layer in partial sections in the act of laser compressingmolding.
 3. The method as claimed in claim 1, wherein the method furthercomprising an act of coating a thermal-resistant varnish layer beforethe act of coating the water-based varnish layer.
 4. The method asclaimed in claim 3, wherein the thermal-resistant varnish layer iscoated on the paper substrate in partial sections and the water-basedvarnish layer is also coated on the thermal-resistant varnish layer inpartial sections.
 5. The method as claimed in claim 3, wherein thethermal-resistant varnish layer is coated on the paper substratecompletely and the water-based varnish layer is also coated on thethermal-resistant varnish layer in partial sections.
 6. The method asclaimed in claim 1, wherein the method further comprising an act ofcoating a non-thermoplastic varnish layer before the act of coating thewater-based varnish layer.
 7. The method as claimed in claim 6, whereinthe non-thermoplastic varnish layer is coated on the paper substrate inpartial sections and the water-based varnish layer is also coated on thenon-thermoplastic varnish layer in partial sections.
 8. The method asclaimed in claim 6, wherein the non-thermoplastic varnish layer iscoated on the paper substrate completely and the water-based varnishlayer is also coated on the non-thermoplastic varnish layer in partialsections.
 9. The method as claimed in claim 1 , wherein the water-basedvarnish layer is composed of 42±2 wt % acrylic copolymer, 3±1 wt % soyabean oil (lecithin) and 55±1 wt % water.
 10. The method as claimed inclaim 3, wherein the thermal-resistant varnish layer is composed of 42±2wt % acrylic copolymer and 55+2 wt % water.
 11. The method as claimed inclaim 6, wherein the non-thermoplastic varnish layer is composed of50-60 wt % acrylic monomer, 40-50 wt % epoxy acrylate oligomer and 5 wt% photo-initiator.